The International Maritime Organization (IMO), the United Nations specialized agency responsible for ship safety, has adopted the International Convention for Safety of Life at Sea (SOLAS), the international maritime safety treaty for the convention of safety of life at sea. This convention covers a wide range of applications, which includes fire resistance of bulkheads and deck heads, which is of critical importance to safety at sea. The recommendations for fire resistance tests are detailed in IMO Resolution A. 754(18), Fire Resistance Tests, Fire Safety On Board Ships. These tests subject fire protection materials (test specimen), which are typically installed in front of a representation of a ships structure (structural core), to a heat release rate which is representative of a cellulose material fire. This cellulosic time/temperature curve is described in the International Organization for Standardization standard, ISO 834. Temperature measurements are taken on the structure core and must satisfy the criteria detailed in Resolution A.754(18) in order to qualify the fire protection material as a fire resisting division. The design and safety of high-speed craft is regulated by the High Speed Craft Codes of 1994 and 2000, adopted by the Maritime Safety Committee of the IMO.
CBG Systems Pty Ltd, with offices in Tasmania, Australia, specializes in the design, development, manufacture and installation of panelized marine structural fire protection systems. CBG has commercialized three unique systems, two for SOLAS ships, and one for High Speed Craft. CBG markets an A-60 class structural fire protection system for fire insulation of deckheads and bulkheads. This prior art system is referred to as its RAS® system. Unlike conventional insulation RAS® is a panel system typically mounted on stiffeners 300 mm below deckheads and 500 mm from bulkheads on the stiffener side of the bulkhead. The standard size of the panels is 1200 mm×900 mm. The panels are mounted in a grid support structure that can be installed in a shipyard at a rate of about 3.5 hours per square meter. This system greatly reduces maintenance costs as compared to conventional surface mounted wrap insulation. Panels can be removed and replaced by one person in less than 5 minutes per panel by way of quarter turn corner plates and screwed on cover strips. All components are 316 stainless steel and do not require secondary corrosion protection. The RAS® system meets IMO requirements as an A-60 Class fire division for steel and aluminum vessel construction.
Although the cellulosic fire curve has generally been accepted as an appropriate test method for many years, it became apparent that certain materials such as petrol, gas or chemicals, have a burning heat release rate well in excess of cellulosic materials such as timber. A time/temperature curve was developed to represent the heat release rate of a hydrocarbon pool fire, and is described in UL 1709 established by Underwriters Laboratories.
The US Navy has developed a unique standard of fire resistance for their surface ships, initially described in MIL-PRF-32161, with revised fire resistance test methods described in MIL-STD-3020. This standard includes the more severe UL 1709 time/temperature curve, and also a requirement for shock testing. This shock testing is designed to be representative of the shock which may be experienced by a ship in operational conditions e.g. missile/mine hit. The shock test methods are described in the Navy Military Specification, MIL-S-901D.
One particular standard of US Navy fire resistance, which is commonly utilized on US Navy surface ships, is “N-30”. This standard involves shock testing of 4 foot×10 foot specimen, fire testing of the shocked and a non-shocked 4 foot×10 foot specimen, and then “full-scale” fire testing of a 12 foot×13.5 foot specimen.
What is needed is an easy to install and remove panel type fire protection system that will meet the requirements of N-30 for use by the US Navy and in other applications requiring protection against severe fire situations.